Appendix C _____________________________________________ Installation and Test Procedures
VAISALA______________________________________________________________________ 387
as when the IFD IF-Input was discon-nected. This verifies that the
dominant noise is indeed coming from the LNA, and not from any of
the subsequent IF amplifiers.
Test Passed
C.21 Calibration and Dynamic Range Check
Test Goal
Verify the receiver dynamic range is in excess of 80 dB.
Special Test Equipment
- KVM connected
- RF signal generator
Reference:.
- See Section 5.5 Pr — Plot Receiver Waveforms on page 163
Test Procedure
1. Run the radar and test signal generator for 20 minutes to allow proper
warm-up of the system prior to the test. This allows the AFC to
stabilize.
2. After warm-up is complete, turn the radiate off, but leave the receiver
on since the test signal generator may be damaged by the transmitter.
The antenna should be elevated to >20 degrees and the azimuth should
be set to point away from any known microwave sources including the
sun.
3. Use the setup terminal to enter the calibration gains, losses, and
transmit power values.
4. Use the "ps" command in the dspx utility to put the RVP900 in manual
AFC control by pressing the "=" key.
For Customer_________________________________ Date__________
For Vaisala___________________________________ Date__________
NOTE
This test requires the injection of an RF test signal over a 100 dB range.
Damage to the LNA could occur. Check the LNA specification to verify
the maximum signal that it can accept. The output from the signal
generator (accounting for cable and coupler losses) should not be allowed
to exceed this value.
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